Rates of women who are opting for preventive mastectomies, such as Angeline Jolie, have increased by an estimated 50 percent in recent years, experts say. But many doctors are puzzled because the operation doesn't carry a 100 percent guarantee, it's major surgery -- and women have other options, from a once-a-day pill to careful monitoring.

A new study suggests that just fingering an item on a store shelf can create an attachment that makes you willing to pay more for it.

Previous studies have shown that many people begin to feel ownership of an item — that it "is theirs" — before they even buy it. But this study, conducted by researchers at Ohio State University, is the first to show "mine, mine, mine" feelings can begin in as little as 30 seconds after first touching an object.

Participants in the study were shown an inexpensive coffee mug, and were allowed to hold it either for 10 seconds or 30 seconds. They were then allowed to bid for the mug in either a closed (where bids could not be seen) or open (where they could be seen) auction. The participants were told the retail value of the mug before bidding began ($3.95 in the closed auction; $4.95 in the open auction).

The study, detailed in the August 2008 issue of the journal Judgment and Decision Making, found that on average, people who held the mug for longer bid more for it — $3.91 to $2.44 in the case of the open auction and $3.07 to $2.24 in the closed. In fact, people who held the mug for 30 seconds bid more than the retail price four out of seven times.

Feelings of ownership develop fast
"The amazing part of this study is that people can become almost immediately attached to something as insignificant as a mug," said study leader James Wolf, who began the work while he was a graduate student at Ohio State. "By simply touching the mug and feeling it in their hands, many people begin to feel like the mug is, in fact, their mug. Once they begin to feel it is theirs, they are willing to go to greater lengths to keep it."

Retailers have been using the try-then-buy tactic for years, said Wolf, who is now an assistant professor of information systems at Illinois State University. For example, car dealers routinely send prospective buyers out on test drives, and pet shop owners encourage people to play with the puppies in the window.

Understanding the attachment this tactic can create could make consumers aware of their own susceptibility, Wolf said.

When testing out new cars, for example, and "going in there knowing that you are going to feel like raising your price, maybe you can be better prepared not to make a hasty purchase that you'll regret later on," he said.

The study was funded by Ohio State's Jensen-Wallin-Young Fund and by Illinois State's Caterpillar Scholars Fund.